Personal identity in the philosophy of kalām

How can I guarantee that I am the same person that I was thirty years ago? A common view among the historians of philosophy is that medieval philosophy offered two kinds of replies to this question, either Aristotelian hylomorphism or Platonic substance dualism. In this paper, I am analysing a third medieval alternative, present in the philosophy of the Basran Muʿtazilite kalām, a completely physicalist theory of personal identity. According to this school of thought, the person is what can be called a “substantial compound” that emerges from the combination of core physical elements. This compound is necessarily identical with the person in question (I call this theory “bundle essentialism”) and, hence, is responsible for the preservation of personal identity.